Ordinarily, a medium to small sized paved area, such as a driveway or parking lot is most efficiently cleared by an operator driving a utility type vehicle to which is affixed at its front end a pusher type snow blade. This blade is typically about seven to eight feet in width and twenty-five to twenty-eight inches in height. It has a vertical cross-section in the form of a somewhat circular segment having a more rounded portion at its top, such as in the shape of a comma (",").
Most often the basic procedure for clearing snow from such an area is, beginning along one side thereof, to make a series of parallel trips in alternate directions, thus progressing in a single lateral direction across the area, all the while moving the mass of snow in said lateral direction by alternating the angled orientation of the blade each time the parallel trip direction is reversed. Even though the blade is appropriately angled so as to move the snow in one desired lateral direction, a portion of the blade must project into the already cleared area in order to avoid returning some snow across the edge of the projecting portion of the blade. For this reason the full width of the blade is not available for moving snow in the desired lateral direction. This deficiency becomes progressively worse as the operation continues, due to the accumulation of cleared snow on top of the adjacent uncleared area. Depending upon the depth of the snow, as much as one-third to one-half of the blade must extend over already cleared areas during much of the operation.
Another problem with the use of equipment of this type is that all of the snow moved must be pushed along the pavement. Only heavier and more complex equipment, such as front-end loaders or bulldozers equipped with special snow shovels, can actually lift and carry large accumulations of snow from one place to another. Thus, the type of equipment described hereinabove is handicapped in clearing the snow from some medium and larger-sized areas, in particular when the snow depth is great.
An additional problem is confronted when equipment of this type must clear the snow from the corner of an area which may have surrounding obstacles, such as retaining walls, buildings, steep banks or combinations of any two of them. When confronted with this situation, the operator of the equipment must get out of the vehicle and resort to hand shoveling.